sportrak problems


hiya,just done head gasket and its running like a sack of sxxt Shok .it pulses when running the rpm goes between 800 and 2000 rpm >Sad .am i going potty? >Sad .it seams to run on 3 cylinders no 4 doesnt seam to do bugger all Scratch one-s head .all put back together as per the daihatsu manual.anyhelp would be gratefully received.cheers not so sportyjay Cray 2

bloody sportrak

also no4 plug is wet and cold,could a lead have failed?.